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Habitability Of Surrounding Planets Affected By Super Flares Of Red Dwarfs: NASA

Red dwarfs -- especially young red dwarfs -- are active stars, producing flares blast out energy

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NASA, tissue
US shutdown delays space missions but NASA not grounded: Report,

Using NASA’s Hubble Space Telescope, astronomers have found that violent outbursts, or superflares, from red dwarf stars could affect the habitability of any planets orbiting it.

Young low-mass stars flare much more frequently and more energetically than old stars and middle-age stars like our Sun, the findings of the study published in the Astrophysical Journal showed.

The findings are based on observations of the flare frequency of 12 red dwarfs.

Hubble is observing such stars through a large programme called HAZMAT — Habitable Zones and M dwarf Activity across Time.

“M dwarf” is the astronomical term for a red dwarf star — the smallest, most abundant and longest-living type of star in our galaxy.

Hubble Telescope. red dwarf
Hubble Telescope. Flickr

The HAZMAT programme is an ultraviolet survey of red dwarfs at three different ages — young, intermediate, and old.

“The goal of the HAZMAT programme is to help understand the habitability of planets around low-mass stars,” explained the programme’s principal investigator, Evgenya Shkolnik from Arizona State University.

“These low-mass stars are critically important in understanding planetary atmospheres,” Shkolnik added.

Stellar flares from red dwarfs are particularly bright in ultraviolet wavelengths, compared with Sun-like stars.

Red dwarf  planet
Artist’s view of planets transiting red dwarf star in TRAPPIST-1 system. Flickr

Hubble’s ultraviolet sensitivity makes the telescope very valuable for observing these flares.

The flares are believed to be powered by intense magnetic fields that get tangled by the roiling motions of the stellar atmosphere.

When the tangling gets too intense, the fields break and reconnect, unleashing tremendous amounts of energy.

The team found that the flares from the youngest red dwarfs they surveyed — just about 40 million years old — are 100 to 1,000 times more energetic than when the stars are older.

This younger age is when terrestrial planets are forming around their stars.

Red dwarf
This illustration shows a red dwarf star orbited by a hypothetical exoplanet. NASA

About three-quarters of the stars in our Milky Way galaxy are red dwarfs. Most of the galaxy’s “habitable-zone” planets — planets orbiting their stars at a distance where temperatures are moderate enough for liquid water to exist on their surface — orbit red dwarfs.

In fact, the nearest star to our Sun, a red dwarf named Proxima Centauri, has an Earth-size planet in its habitable zone.

Also Read: NASA Plans For Science Payloads For Delivery To Moon

However, red dwarfs — especially young red dwarfs — are active stars, producing flares that could blast out so much energy that it disrupts and possibly strips off the atmospheres of these fledgling planets. (IANS)

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Scientists to Detect and Count Stranded Whales from Space

It is hoped that in the future the technique will lead to real-time information as stranding events happen

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Scientists, Whales, Space
Now we have a higher resolution 'window' on our planet, satellite imagery may be a fast and cost-effective alternative to aerial surveys allowing us to assess the extent of mass whale stranding events, especially in remote and inaccessible areas. Pixabay

Analysing satellite images may help scientists detect and count stranded whales from space, new research has found.

In a study, published in the journal PLoS ONE, researchers tested a new detection method using Very High Resolution (VHR) satellite images from space tech compnay Maxar Technologies.

“This is an exciting development in monitoring whales from space,” said lead author Peter Fretwell at British Antarctic Survey.

“Now we have a higher resolution ‘window’ on our planet, satellite imagery may be a fast and cost-effective alternative to aerial surveys allowing us to assess the extent of mass whale stranding events, especially in remote and inaccessible areas.”

Scientists, Whales, Space
In a study, published in the journal PLoS ONE, researchers tested a new detection method using Very High Resolution (VHR) satellite images from space tech compnay Maxar Technologies. Pixabay

It is hoped that in the future the technique will lead to real-time information as stranding events happen.

The study by scientists from British Antarctic Survey and four Chilean research institutes, could revolutionise how stranded whales, that are dead in the water or beached, are detected in remote places.

In 2015, over 340 whales, most of them sea whales, were involved in a mass-stranding in a remote region of Chilean Patagonia.

The stranding was not discovered for several weeks owing to the remoteness of the region. Aerial and boat surveys assessed the extent of the mortality several months after discovery.

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The researchers studied satellite images covering thousands of kilometres of coastline, which provided an early insight into the extent of the mortality.

They could identify the shape, size and colour of the whales, especially after several weeks when the animals turned pink and orange as they decomposed.

A greater number of whales were counted in the images captured soon after the stranding event than from the local surveys.

Scientists, Whales, Space
“This is an exciting development in monitoring whales from space,” said lead author Peter Fretwell at British Antarctic Survey. Pixabay

“The causes of marine mammal strandings are poorly understood and therefore information gathered helps understand how these events may be influenced by overall health, diet, environmental pollution, regional oceanography, social structures and climate change,” said study co-author and whale biologist Jennifer Jackson at British Antarctic Survey.

Also Read- Climate change, Pollution Causing Irreversible Damage to New Zealand’s Marine Environment

“As this new technology develops, we hope it will become a useful tool for obtaining real-time information. This will allow local authorities to intervene earlier and possibly help with conservation efforts,” Jackson said. (IANS)